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I have a bookshelf that seems to be made out of wood that has a polymer/plastic finish already on it. What is the best way for my to Paint it?

I know that for unfinished wood furnshings, I would follow a steps like this:

1) Sand paper (150 to 220 grit)
2) Dust off sand residue
3) Apply primer
4) Apply Paint

What would I need to do differently when working with wood finished with plastic/polymer? What brands of paint are the most promising? Thank you!
 

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Irutter:

After you sand and clean up the dust, I would use an oil based primer for better adhesion and a stronger undercoat. Use a Q-tip to paint a small area of an inconspicuous spot with the primer first, give it a coupla days to dry completely and then scratch at the primer with a sharp paint scraper. If the primer is adhering properly, it won't break off in a large chip. You should be able to scrape the primer off with the paint scraper without it letting go of the substrate. If you find that you can scrape the primer down to the substrate without it all breaking off in a big chip, then you're ready to prime the whole bookshelf.

Shelves are working surfaces and you need to use the HARDEST drying paint available to provide good service on them. If you just use any latex paint, the shelf surfaces will be soft and dust and dirt will become embedded in the paint making the shelves look dirty.

Oil based paints dry to harder films than latex paints, but are generally no longer available for sale. However, you can still buy high gloss alkyd paints for painting metal. If you want a high gloss paint on your bookshelf, I would use a high gloss alkyd paint that will probably say "For use on metal ONLY" on the can. That wording is there because alkyd paints were taken off the market a few years ago, but are still allowed in high gloss for painting metals (at least they are here in Canada). The paint is exactly the same as before, and you can use it to paint your bookshelf if you want a high gloss finish on it.

If you can find a paint called Monamel at a Colourwheel Paint store, Frazee Paint store, Kwal Paint Paint store, Parker Paint store or if you living in Canada, a General Paint store, then that would be my second choice for a top coat.

Finally, my third choice would be to use any company's "Porch & Floor Enamel" as the top coat over the alkyd primer. That way, you're at least getting that company's hardest drying latex paint. Porch & Floor paints are made with acrylic resins that "crosslink". You apply the paint just like any other paint, but for a month or more after the paint dries, chemical crosslinks form inside the paint film that make the paint film harder and stronger. So, if you use a "Porch & Floor Enamel", don't expect it to be hard right off the bat. You need to give it time for that crosslinking to occur.
 

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Sounds more like a Laminate shelving board.
Cheap partical board with laminate over it.
What makes you think it's real wood?
Laminate would require sanding, a bonding primer then paint.
An latex enamel paint would work fine.
 

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Sounds more like a Laminate shelving board.
Cheap partical board with laminate over it.
What makes you think it's real wood?
I thought that too, but the guy said "I have a bookshelf that seems to be made out of wood..." and I think that word "wood" still means "real wood".

My sister has real oak cabinets in her living room which she bought shortly after she purchased a house with her former husband. So, real wood cabinetry does exist.
 

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I've been expirementig with PPG Breakthrough on different surfaces like what you describe. It's a super tough (rated for floors with forklift traffic) acrylic coating with superb bonding capabilities. Yesterday I tried it on some laminate cabinet finished ends and it stuck like chuck. Might be a good choice for your project. Requires no primer on laminated or previously painted surfaces, just a scuff sand and clean.
 

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MY self, I would wash it clean. (sounds weird i know) Just a rag with warm water is fine. Sand while its still wet use a med-fine sanding pad. Wipe it all clean and dry. Prime many options here. Oil is used a lot i prefer shellac. I look at it like this is latex smells 2/10 oil is around 6/10 shellac is 8/10. Reason for shellac is 1 unlike oil the smell is gone in under 20 min. It will also be cured in under 20 min. So no worries of runs and sags like oil. Key with shellac sticks to anything. I mean anything. I use it as my primer with cabinets. As far as top coat this here will be very ones personal preference. I would recommend for a DIYer like you a product called All Surface Enamel. It dries hard and the key is fast. Not so fast it will be hard for you to use but fast enough runs and other pesky paint problems wont occur on you as much. Here is a link to Primer and Finish

Primer http://www.sherwin-williams.com/hom..._diy.white_pigmented_shellac_primer.650133499 Keep in mind you don't need the primer to be solid so u cant see the color underneath that does not matter. Its just there to bite the surface so your top coat has some teeth(wont scratch off) solid color will come from 2 top coats.

Top coat http://www.sherwin-williams.com/homeowners/products/catalog/all-surface-enamel-latex-base/

top coat can be made to any color you like. If u want i can send you pictures of things i have done with this exact method. I do this for a living buy the way just so you know. Best of luck with your project.
 

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Nestor is in Canada and it's harder to get oil based paint there than in the US, not sure where you are. That said, oil based paint will yellow in time, so it's a poor choice if you want white in the first place.
 

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  1. Clean it.
  2. Scuff sand it with 100 or 120 grit.
  3. Wipe the dust off with a damp cloth or paper towel.
  4. Prime with a good bonding primer. Insl-X STIX or BIN are both very good, but you could use lots of other products successfully.
  5. Sand out the brush marks or roller stipple.
  6. Paint. Lots of acrylics are soft and sticky for a long time. I've put stuff on shelves painted with Pittsburgh's Manor Hall semi-gloss within a day of painting with good success. On the other hand I've painted shelves with Behr semi-gloss and had them remain sticky for months. You could go with something harder, like Cabinet Coat and similar products, or something oil-based, but you'll have to wait a lot longer if you go with an oil.
 

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Depending on where you are, I would use Cabinet Coat from Insl-x (a Ben Moore company) or California Ultraplate. You should be able to get Cabinet coat from any Ben Moore dealer. Also, any True value or Do It Best Hardware store should be able to get it. Both products are only available in white or pastel colors. Advance from Ben Moore or Nextech from California would be a good option if darker colors are desired and you don't use an oil base product.
 

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That said, oil based paint will yellow in time, so it's a poor choice if you want white in the first place.
With utmost respect for Stick\Shift's knowledge and experience, this DIY Q&A forum serves an educational purpose in that the newbie homeowners in here learn from the posts that the more experienced people write. I therefore feel an obligation to clarify what Stick\Shift wrote so as to illuminate the issue.

OIL BASED PAINTS YELLOW...

...but that only happens if the paint is in a location where there isn't very much natural light...

...and the yellowing is completely reversible. That is, if you take an old yellowed painted cabinet out of your basement and leave it in front of a picture window for a few weeks, the yellowish discolouration of the oil based paint on the cabinet will completely disappear.

This is exactly what museum curators do prior to putting old oil based paintings on display. Most museums have far more paintings than they can put on display at any one time, so most of a museum's paintings spend years in storage with little or no natural light. This causes a problem for the museum curator who wants to display the painting the way the artist painted it, not in it's yellowed condition.

This Article of the Journal of the American Institute of Conservation:

http://cool.conservation-us.org/jaic/articles/jaic24-02-002.html

(who are the people who restore old artifacts as best they can to their original condition) investigates how old oil based paintings were allowed to yellow in the dark before being exposed to indirect sunlight for a period of time (up to a few months).

Figure 1 of that article summarizes the results.

Line #2 on that chart is called a "copal medium". Copals are plant resins, kinda like amber (which is dried up tree sap) that are dissolved in drying oils like linseed oil or Tung oil to make an "oil based" paint. Years ago, the only difference between varnish and oil based paints was that varnish had better quality copals and more of them in it, which made varnish dry to a harder stronger film than paint. Paint, on the other hand had pigments added to it to give it colour and opacity, and so the clarity of the copals in paint was of less importance than in varnish, where transparency was important.

Line #13 in Figure 1 is an alkyd paint; no different than the alkyd paints that we used to buy in paint stores only a few years ago.

In each case on that graph, "oil based" paints that were allowed to yellow in the dark, returned to their original "non-yellowed" condition after only a few weeks exposure to indirect natural light. It didn't even need to be direct sunlight, like the stuff that gives you a sunburn. Indirect light was sufficient. So, you could put that cabinet from your basement in the shade of an old tree and the indirect sunlight would reverse the yellowing.

So, yellowing happens in oil based paints, but to say it always happens is wrong. Yellowing in exterior oil based paints is a non-issue because the paint is exposed to natural light all the time it's outdoors.

And, that JAIC study shows that the paint can be allowed to yellow repeatedly, and each time it will return to it's non-yellowed condition upon exposure to natural light.

Hope this illuminates (no pun intended) "yellowing" in oil based paints.
 
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